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Technical => Spud Miller's Cave => Topic started by: jeff/21 on June 03, 2016, 04:15:16 PM

Title: electric lean-out
Post by: jeff/21 on June 03, 2016, 04:15:16 PM

i have a question can i connect electric lean -out on the port that's in back of the spool ? 406 sbc 6-71 with an old style 4 butterfly hat runs way too rich idle

Title: Re: electric lean-out
Post by: Spud Miller on June 03, 2016, 04:28:43 PM

 This must be a Hilborn type setup?

 In order to control all that fuel with that type of deal, you really need an "idle bypass" off that port on the metering valve...a check valve set to 5-7 PSI. It only works when the throttle is shut or barely open, not WOT. It'll off-load a bunch of fuel for you at idle and solve your problem.

 Using an electronic lean out there probably wouldn't be the best setup for an all around good idle. You'd have manage it being on or off somehow at the right times. A regular old check valve takes care of itself. Plus, the check valve provides some resistance to flow which is needed to make some of the fuel continue on to the nozzles. An electronic valve would be a big old "leak" (even if you put a pill in it) and idle flow would be sketchy at best.

 Spud

Title: Re: electric lean-out
Post by: ricardo1967 on June 03, 2016, 07:28:02 PM

I'm just trying to learn here... Couldn't this be addressed by adjusting (rotating) the barrel valve?

Title: Re: electric lean-out
Post by: jeff/21 on June 03, 2016, 07:35:19 PM

thank you! yes it's a Hilborn system, i thought that that a regular check would lean it too much at top end

richardo1967  I've tried  but the the only way i can get it to run clean is by playing with the fuel shut-off

Title: Re: electric lean-out
Post by: ricardo1967 on June 04, 2016, 05:33:29 AM

Got it. Good luck Jeff!

Title: Re: electric lean-out
Post by: dreracecar on June 04, 2016, 07:47:26 AM

Quote from: jeff/21 on June 03, 2016, 07:35:19 PM

thank you! yes it's a Hilborn system, i thought that that a regular check would lean it too much at top end

richardo1967  I've tried  but the the only way i can get it to run clean is by playing with the fuel shut-off

 Idle check is blocked off at open throttle and has no effect on top end performance. Top end delivery control is done with a high speed check and the can be tuned with jets and shims.

Title: Re: electric lean-out
Post by: jeff/21 on June 04, 2016, 11:31:26 AM

the port i'm asked about is after the spool and before the injector lines and leak here will affect the fuel curve , on methanol i didn't have a problem but the customer wants to run gas.

Title: Re: electric lean-out
Post by: dreracecar on June 04, 2016, 11:55:26 AM

Why did you not mention the GAS part????
Idle slot is much smaller for gas and would be better off changing to a "GAS" spool then to try an add gimmicks

Title: Re: electric lean-out
Post by: jeff/21 on June 04, 2016, 01:39:37 PM

been changed #54